... ,galvanized,polished,or no finishHole shapeRound, Square, Slot, Triangle, Long round, Scale, Diamond, Oval, Hexangular, etcHole ... ...MarginNo margin/ Common margin/ Special requirementDiameter0.5-100mmThickness0.5-25mmDimensionwidth equals to or less than 1500mm ... environmental noise control barriers, architectural objects, walls, generator room, factory premises, and other noise acoustic noise ...